Power electronics devices often include a half-bridge arrangement of a high-side power switch, a low-side power switch, and a switch node between the power switches. In some examples, the high-side power switch is an n-type transistor that conducts electricity when the voltage at the control terminal is sufficiently higher (i.e., by a threshold voltage) than the voltage at the switch node. When the high-side power switch conducts electricity, the voltage at the switch node may approach a voltage level of the high-side voltage supply circuitry. In some examples, the voltage level of the high-side voltage supply circuitry may be tens or hundreds of volts higher than the voltage level of the low-side voltage supply circuitry.
The power electronics device may include gate driver circuitry configured to deliver control signals to the control terminal of the high-side power switch. To generate control signals with a voltage level that is higher than the voltage level at the switch node, which may approach the voltage level of the high-side voltage supply circuitry, the gate driver circuitry may receive electricity from floating voltage supply circuitry. The floating voltage supply circuitry may be configured to receive power through a blocking diode configured to conduct electricity from auxiliary voltage supply circuitry. The floating voltage supply circuitry may also be configured to receive power through a bootstrap capacitor configured to conduct high-frequency signals from the switch node to the floating voltage supply circuitry.
In some examples, the gate driver circuitry may be configured to receive shifted control signals from level-shifter circuitry. The level-shifter circuitry may be configured to receive the control signals and generate shifted control signals by increasing the voltage of the control signals while maintaining the information encoded in the control signals. The level-shifter circuitry may be configured to increase the voltage of the control signals based on a voltage of the floating voltage supply circuitry. The gate driver circuitry may be configured to generate and deliver higher-power control signals (i.e. driving signals) to the control terminal of the high-side power switch by increasing the power of the shifted control signals received from the level-shifter circuitry. In some examples, the control signals may include pulse-density modulated (PDM) signals, pulse-width modulated (PWM) signals, pulse frequency modulation (PFM) signals, and/or any other type of control signals.